An electronic device such as a portable telephone having waterproofness is provided with a containing portion that contains detachable electronic components such as a battery in a casing. The containing portion is water-tightly closed by a lid body.
For example, in order to make the lid body detachable, there has been proposed an electronic device using a rotary lock operation piece that can lock the lid body in the casing.
The lock operation piece is rotatably attached to the casing by inserting a screw into a through-hole penetrating a wall of the casing.
In order to prevent entrance of water into the casing from the through-hole, a waterproof structure such as packing is required around the through-hole. This increases the number of components of the electronic device, which makes configurations of the respective components complicated. Furthermore, frequent operation of the lock operation piece, time degradation or the like degrades waterproofness of the waterproof structure, so that there is a possibility that water enters the casing from the through-hole.
Thus, there has been desired an electronic device including a lock operation piece that locks a lid body such as a battery lid while having waterproofness.